window.onload = function () {
  $('login_form').onsubmit = function () {
    //inline_results();
      alert('bb');
    return false;  
  }
}

//function inline_results() {
//  new Ajax.Updater ('validation_errors', base_url+'login/validate_login', {method:'post', postBody:'username='+$F('username')+'&password='+$F('password')});
//  new Effect.Appear('validation_errors');
//}